Framboidal chalcocite from White Pine, Michigan

Alyanak, Nancy; Vogel, Thomas A.

doi:10.2113/gsecongeo.69.5.697

Cited by 3 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Without detailed study chalcocite spherules from the Kupferschiefer were interpreted as resulting from the replacement of framboidal pyrite (Schouten 1946;Rentzsch 1974) or carbonate spheroids (partly calcareous algae) (Siegl 1941;Mayer and Piestrzynski 1985). However, the laboratory experiments of Farrand (1970) and also the observations of Alyanak and Vogel (1974) on the White Pine Mine have shown that copper sulphide framboids can be primary precipitates. Farrand (1970) has proved that the same condi-tions can produce both pyrite and copper sulphide framboids.…”

Section: Discussionmentioning

confidence: 99%

“…Other minerals are rarely found in the form of framboids; some of them could be oxidation products of pyrite (magnetite, limonite) or of its precursors (greigite). Until now the only known exception was the framboidal cores of chalcocite grains from the White Pine Mine, Michigan, described by Alyanak and Vogel (1974) and regarded by them as primary. The formation of copper sulphide framboids can, with some caution, be regarded as similar to the formation of pyrite framboids.…”

Section: Formation Of Pyrite Framboidsmentioning

confidence: 99%

See 1 more Smart Citation

Primary copper sulphides from the Kupferschiefer, Poland

Sawłowicz

1990

Mineral. Deposita

View full text Add to dashboard Cite

Abstract. Finely dispersed, primary, copper sulphide mineralization from the zones of Cu-S paragenesis in the Zechstein copper-bearing shale from the Fore-Sudetic Monocline, Poland, was studied. It is represented mostly by small spherules and framboids (5 to l 0 btm in size) and framboidal clusters of digenite, chalcocite and minor covellite, dispersed throughout the whole shale but especially abundant in the organic-rich laminae. Detailed microscopic and chemical (microprobe) descriptions of this mineralization are given and a comparison with pyrite framboids is presented. Digenite usually dominates over chalcocite among dispersed mineralization, in contrast to that observed in larger diagenetic grains. The rarity of copper sulphide framboids, in comparison with spherules, can probably be explained by the fast process of their homogenization. The textures, chemistry and some different features from pyrite framboids suggest that the copper sulphides in Fe-poor zones of the Kupferschiefer are primary precipitates. The results of the study suggest that the beginning and probably the main stage of the ore mineralization process took place during the sedimentation and/or early diagenesis of the Kupferschiefer.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Formation Of Pyrite Framboidsmentioning

confidence: 99%

Primary copper sulphides from the Kupferschiefer, Poland

Sawłowicz

1990

Mineral. Deposita

View full text Add to dashboard Cite

show abstract

“…Minor amounts of covellite, bornite, and pyrite are also present [8]. Most of these sulfide minerals are bound in micrometer-sized framboids enmeshed in the organic residues in the black shale [9][10][11].…”

Section: Introductionmentioning

confidence: 99%

Geochemistry and Microbiology of Atacamite-Paratacamite Biofilms Floating on Underground Brine and Petroleum Pools in the White Pine Copper Mine, Michigan (USA)

Robbins,

Stanton,

Young

2023

Micro

View full text Add to dashboard Cite

At depth in an abandoned tunnel of the White Pine Copper Mine, green films of the Cu-OH-Cl minerals atacamite and paratacamite were found on standing pools of brine. Some pools were also coated with a thin layer of petroleum. Green films of atacamite were composed of individual blebs that averaged 20 μm in diameter and enclosed mixed colonies of Gram-negative, short rod-shaped, and sheathed filamentous bacteria. Carbon δ13C values in the atacamite–paratacamite mixtures reflect the isotopic values of bacteria and minor amounts of petroleum mixed with the minerals. Heterotrophic bacteria are interpreted to be using petroleum as a carbon source and may be catalyzing the precipitation of the copper hydroxy chloride minerals or acting as a template.

show abstract

Comment on “Oil shales, evaporites and ore deposits” by Hans P. Eugster

Sawłowicz¹

1986

Geochimica et Cosmochimica Acta

View full text Add to dashboard Cite

Framboidal chalcocite from White Pine, Michigan

Cited by 3 publications

References 0 publications

Primary copper sulphides from the Kupferschiefer, Poland

Primary copper sulphides from the Kupferschiefer, Poland

Geochemistry and Microbiology of Atacamite-Paratacamite Biofilms Floating on Underground Brine and Petroleum Pools in the White Pine Copper Mine, Michigan (USA)

Comment on “Oil shales, evaporites and ore deposits” by Hans P. Eugster

Contact Info

Product

Resources

About